(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Estimate a reynolds number for a pipe of 0.3m internal diameter, carrying water at a rate of 71 m/s, and say what that says about the likely nature of the flow.

2. Relevant equations

Re = (density x L x velocity of flow)/coefficient of dynamic viscosity for water

Viscosity of water = 8.9 x 10^-4 kg/m s

density of water = 1000 kg/m^3

3. The attempt at a solution

Well, I have produced a result of some 27 million, which seems excessive to me. Possible mistakes: I used the diameter of the pipe as L. Also, the flow speed is something I calculated in a previous question, so could potentially be wrong. The speed is just due to potential energy coming from a reservoir exactly 500m higher up, where pressure is atmospheric only.

Does anything sound wrong with this solution? I have no reference for typical reynolds numbers in these situations...

Thanks in advance

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# Homework Help: Reynolds number

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